Synchronizing device for ignition timers



Jan. 8, 1929.

J. T. FITZSIMMONS ET Al.

sYNcHRoNIzING DEVICE FOR IGNITION TIMERS Filed Nov. 18, 1927 m l l L V,preferred vform of embodiment of the presentV Patented Jan. 8, 1929.

UNlTEQ STATES satana "reifen,

JOHN T. FITZSIMMONS AND-'i/VILLAM D. SHROPE, OF ANDERSON, NDIANA, ASSIGNORS TO DELCO-REMY COREORATON, OF DAYTON, OHO, CORPORALINy OF DELAWARE.

siicnaoivrzine nnvicn rea ieiliirioii Tri/inns.

V.Application filed November 18, 1927. Serial No. 234,098.

This invention relates to ignition timers for internal combustion engines and more particularly to the type of ignition timer which comprises a plurality of circuit interrupters which are operated alternately inv recurrent sequence. One example of` ignition apparatus to which the present -invention may be applied is that shown in the co-pending application 'of William D. Shrope7 Serial No. 126,413, i'iled August 2, 1927. v

One object of the present invention is to provide a tool'which may be readily applied to the ignition timer and which will facilitate the determination of the extent to which the angular relation'between the circuit interrupters should be adjused in oider to obtain the proper time relation between the operations of the circuit interrupters.

In the present invention this object is preterably obtained by providing a synchronizing tool having an arm which may be readily attached to the ignition timer cam in predetermined relative positions thereto dev,pending on the direction of rotation of the timer cam when operating to provide ignition, said arm having a purality of sets ott graduation spaced apart a predetermined distance dependent upon the angular spacing of the circuit interrupters. A certain mark or part of the ignition timer housing cooperates with these sets of graduations in order to determine to what extent the angular relation between the interrupters should be varied in order to obtain the correcttinie relation between theoperations of the interrupters.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings', wherein a invention is clearly shown.

In the drawings: l

Figs. 1 and 2 are plan views showing ditferent positions of the interrupters of an ignition timerhaving a plurality of circuit interrupters normally operated by a cam which rotates in a clockwise direction, the cam carrying a synchronizing device embodying the present invention.

Figs. 3 and 4 are views similar to Figs. 1 and 2 respectively, showing an ignition timer in which the cam' normally rotates in a counterclockwise direction.

F ig. 5 is a cross sectional-view showing.A the manner of attaching the synchronizing` device to the timer cam. Fig. 6 is a sectional view on line 6-6 of Fig. l

Fig. 7 is a detail view showing the pivotal connection of the circuit breaker lever with the mounting plate. g

Fig. 8 is a detail view of the Vcircuit breaker lever and its spring connector.

Fig. 9 is a plan view ,of the circuit breaker lever supporting'bracket. y

The ignition timer shown in the drawings comprises a cup-shaped housing which supports a plate 21 having two apertures 22 and 23 through which extend upwardly the upstandingears 24 and 25 of -a terminal plate 26 secured to the underside ottliep'late 21 and insulated therefrom by suitable insulating members, one of which is shown at 27 in Fig. 5. The ears 24 and `25 provide insulated terminals for the two circuit interrupters which are connected in parallelr in an ignition primary circuit and are operated alternately to complete and interrupt the circuit from the battery to an ignition coil. The interrupters are operated alternately by a cam, the number of lobes of which equals one-half the number of sparking impulsesin each engine cycle, for eX- ample,` four cam lobes where the engine requires eight sparks occurring at equal intervals during each engine cycle. o n

One ot the circuit interrupters comprises a breaker lever `30 having a non-conducting hubr31 pivoted upon a stud 32 which is carried by an adjustable breaker lever plate 33. The lever 3() carries a rubbing block 34 for engaging the cam 35 which rotates centrally within the housing 20. The lever 30 carries a contact 36 for engaging `a stationary contact 37 carried by a .contact bracket 38 having a hole 39 through whichthe stud 32 may extend to provide a ulcrum for the bracket 38 coaxial with the ulcrum for the breakerl lever 30. As shown in FigureY 8, the non-conducting ybushing 31 spaces the lever 3() from thebracket 38 so that electrical contact is not made between these parts except by the contacts 36 and 37. A spring 40 which is attached to the lever 30 bya rivet 41 which also secures a rubbing block 34, is attached by a screw 42-to the ear 24 and the spring is so biased as to urge the lever 30 in a counterclockwise direction so insists;

as to maintain the contact 36 in engagement with the contact 37 and tend to maintain the rubbing block 34 in engagement with the cam 35. v Y

The bracket '38 is maintained in adjusted position relative to the plate 33 by a. screw 43 having Vthreaded engagement with the plateL 33"and passing vthrough a slot 44 in vthe bracket 38. Thebracket 38 has a slot 45for receivinga -disc 46 provided with a screw-driver slot and with an eccentric shank 47 ,which is rotatably secured to the plate 33. To adjust the bracket 38 relative to the plate 33, the disc 46 is turned, the screwl 43 being loosened, inorder to locate the rub bing block 34 in such position radially of the cam 35 that the desired amount of con tact separation will be obtained. lVhile this adjustment is made, the cam 35 will engage the block 34 so as to move it farthest fromV the axis of the cam. Y

The other interrupter .comprises a breaker lever 50 having a non-conducting bushing 51 journalled upon a vfulcrumed stud 52 which is attached to the stationary supporting plate 21. lThe lever 50 carries a rubbing block 54 for engaging the cam 35 and a movable contact 56 Vfor engaging a stationary contact 57 carried by a contact bracket 58 similar to the bracket `38. The bracket 58 is insulated from the lever 50 and is fulcrumed about the fulcrum stud 52 bya construction similar to that described with reference to bracket 38. The bracket 58 is held in adjusted position relative to the stationary vplate 21 by a screw 63 having threaded engagement with the plate 21 'passing through a slot 64 in the bracket 58. A spring 60 which is attached at one end to the lever 50 and at the other end to the ear 25 by a screw 62 is biased for moving the lever 50 ina clockwise direction 'in order 'that the cam may be engaged by the rubbing block 54 or the stationary contact 57 engaged by the movable contact 56.

In order to adjust theA rubbing block 54 relative to the cam 35 in order to secure the desired amount of contact separation, Vthe screws 53 are loosened and an eccentric disc 66 received by a slot 65 in the bracket 58 is turned about its eccentric shank 67 which rotates in a bearing provided by the bracket 21. When. the desired amount of contact separation has been obtained the screw 63 is tightened. W'hile this adjustment is being Ymade Vthe block 54 is held by the cam 35 farthest from the axis of the cam.

In order to adjust the angular relation be- Vtween the two circuit interrupters relative to the cam 35, mea-ns are provided for adjustingr the rubbing block 34 relative to the rubbing block 54 and angularly of the cam 35. For this purpose, the plate 33 is fulycrumed on a screw 7 0 attached to the plate 21 and is held in a desired position of adjustment relative to the plate 21 by screws 71 and 72 which pass through slots 73 and 74 respectively in the plate 33 and have threaded Aengagement with the plate 21. The slots 73 and 74 are arcuate and are concentric with the screw v70. To facilitate turning the plate 33 whilev adjustments are being made, the plate is' provided with a slot 7 5 for receiving a screw-driver slotted disc 76 having an eccentric shank 77 Vjournalled in a bearing provided by the plate 21. j

The present invention provides a device for determining the Vdegree of angular adjustment'of the plate 33 and rubbing block 34 necessary to give the proper relation between the operations ofA theV circuit inter' rupters. The device will be known hereafter as a synchronizing device, meaning a device for determining the degree of adjustment to obtain the required synchronism or time relation between theV operations of the circuit interrupters.

The` synchronizing device comprises a sector plate 8O carried by an arm 81 attached. to a hub 82 which is adaptedV to lit around the cylindrical extension 83 of the cam 35. The

extension 83 is provided with a flat 84 and is adapted to be received by a similarly shaped recess in a rotor block of a distributor rotor Y not shown. It is well understoodvby those skilled in this art that'the flat 84 provides for correctly locating the distributorrotor relative to the cam and provides connection between'the cam and rotor. This flat which will be hereinafter rreferred to 'as the distributor rotor locating and driving means provided by the cam, is utilized in locating the segment in a certain position relative to the cam 35. The arm 81 is shapedto provide a flange 85 which retains a sliding bar 86 received by a notch 87 in the hub 82. rl'he bar 86 is provided with edge surfaces and 89 which are related in such manner asy to adapt the device for ther type ofignition timer shown whether it is constructed for clockwise orl for' counterclockwise rotation.

After the contact brackets 38 and 58have been adjusted in order to give the correct` amount of contact separation, thefplate 33` may be adjusted relative to the plate 21 through the aid of a synchronizing tool which is used in the following manner: The hub 82 is placed overthe cam extension 83,` the bar 86 having been located symmetii. cally of the arm 81 as shown in 6. If the ignition timer cam 35 normally rotates in a clockwise direction, the bar' 86 is moved into the position shown in Fig. 1 relative to the cam so that its edge surface 88 will engage tlie fiat 84 of the cam. turned in a clockwise direction until the contact 56 just separates from the contact 57. 1

The location of a point on a set of graduu ations 9() of the segment 8O with respectto a part of the timer housing 20 such as the edge 91 defining a notch for receiving the The cam is j terminal arm 26a of the bridging plate 26, is noted. For example, the mark 16 of the graduations 90 may be opposite the edge 91. The cam is rotated further in a clockwise direction until the segment 80 occupies the position shown infFig. 2 in which the point 16 of its set of graduations 92 is located adjacent the edge mark 9 1. While the segment is maintained in this posit-ion, the

' has been made again for Contact se aration the adjustment for synchronism may be repeated. These adjustments should be confined to the adjustments of the plate 33 and the bracket 38. The bracket 58 should not be re-adjusted.

It will be noted that when the edge surface 88 of the bar 86 is in contact withthe l fla-t 84 of the cam extension 83, that portion of the bar 86 which is exposed to view. carries an arrow 100 which points in a clockwise-direction. This arrow will indicate that the tool has been attached properly kto an ignition timer, the cam of which is intended to rotate in a clockwise direction.

Figs. 3 and 4 show how the synchronizing tool is used for the same type of ignition timer, the cam of which rotates normally in a. count'erclockwise direction. As known to those skilled in this art, the only difference between ignition timers `adapted for clockwise or counterclockwise direction of rotation respectively is in the angular relation between the distributor rotor and the timer cam. It will be noted that the angular relation between the fiat 84a 4of the timer cam 35akshown in Fig. 3 adapted for counterclockwise rotation bears a relation to the lobes of the cam which is different from the relation between the fiat 84 and the lobes of the cam 35. It will be noted that the angular difference between the relation of the flats 84 and 84a relative to the cam lobes is an angle equivalent to the angle of the active part of a cam lobe.

When the tool is used with a timer whose cam is intended to rotate counterclockwise, the slide bar 86 is moved into such position that its edge surface 89 will engage with the flat 84a and the exposed portion of the slide bar will reveal an arrow 101 pointing in a counterclockwise direction to indicate to the user that a tool has been properly applied to the cam of an ignition timer intended for counterclockwise rotation. The. tool is used in a manner similar to that with which it is usedin the ignition timer shown in Figs. l and 2 with the exception that a certain mark of its center graduations 92 will be located opposite the edge mark 91 at the time the contacts 56 and'57 begin to separate when the cam 35a is turned in a counterclockwise direction as shown in Fig. 3. lf 16 is the number of the graduations 92 ywhich is opposite the edge mark 91 of the timer at the instant of separation of contacts 56 and 57, the segment' 8O is turned in a counterclockwise direction until the mark 16 of the center graduations 90 is located opposite the mark 91 as shown in Fig. 4. Then after loosening the screws 71 and 72, the plate 33 is rotated about its pivot by turning` the eccentric disc 76 until the. rubbing block 34k will be moved in a clockwise direction back against the lobe of the cam 35a sufficiently to cause the contacts 36 Vand 37 to separate. Then the screws 71 and 72 are tightened. In case this adjustment alters the predetermined adjustment of the bracket to effect the correct amount of contact separation7 'im i the bracket 38 is re-adjusted to give the cori rect amount of contact separation and then the adjustment of the plate 33 may berepeated if necessary in order to giverthe correct synchronism. n

The graduations on the synchronizing tool may represent degrees of rotation of the engine crank shaft and ytherefore the tool may be used to indicate how many degrees the interrupters are out of synchronism. The sets of graduations are spaced apart angularly with respect to the axis of the cam a predetermined angular distance depending upon the type of double breaker timer with Vwhich the instrument is to be used. For

example, if the timer isi-intended to provide sparking impulses for an eight vcylinder engine having equal firing intervals, then the interrupters should be synchronized so that they will operate alternately every 45 of rotation of the cam. Consequently the angular spacing between the sets of graduation and 92 is 45.

If the eye cannot detect Vthe instant of contact separation in orderto obtain an ac-` curate synchronizing adjustment, the ignition circuit which includes the timer, the ignition coil and the battery is closed with an ammeter in the circuit. The Ainstant of contact separation will be indicated when the ammeter needle registers zero. f

While the form of embodiment 0f the present invention as herein disclosed, constitutes a preferred form, itis to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows: 1. A synchronizing tool for an. ignition timer having two interrupters, said tool comprising a rotatable plate member adapted to be attached to the operatingfshaft of the timer and having 'ai plurality of sets of graduations 'spaced angularly `a prede termined distance depending on the required synchronism between .the interrupters, a certain mark or part of the timer cooperating With one of the sets of graduations kto point to a mark of said set of graduations When one of the interru eters begins to function,the other interrupter being in desired synchronisin when the corresponding Ygraduation mark on the other set of vgraduatio'ns is adjacent said timer mark or part at the instant the other interrupter begins a similar function.

Y 2. A synchronizing tool according to claim l in Which meansr are provided for securing the graduated plate tothe operating shaft in a certain angular relation When the operating shaftnormall-y rotates in one direction, and in a different predetermined angular relation When-the operating shaft normally rotates in the opposite direction, whereby the tool may be. adapted tobe used with timers Whose operating shafts are intended to rrotate clockwise or counterclock- Wise.

3. A synchronizing tool according to claim l and having a hub which supports the graduated plate and which is adapted to iit over that part ofthe timer operating cam Which supports the distributor rotor, said part of the cam having a rotor locating and driving portion, said tool having a plurality of means for drivingly connecting the hub With the rotor locating part 'of the cam in order to locate the graduated plate in diferent`an- Vgular relations to the cam dependent on Whether the timer cam is intended for clockwise or counterclockwise rotation.

4. A synchronizing VVtool according to claim l and having ahub Which supports the graduatedplate and which is adapted to fit over a cylindrical extension of the timer operating cam Which extension supports the distributor rotor, said extension or" the cam having a `flat side surface by which the rotor 'is located' and driven, a bar slidable through Va slot in the hub and. having along one side tivo Wedging surfaces located in a predetermined angular rela-tion, each, `Wedging surface being adapted vto engage theflat of the cam extension, said bar having a straight edge along the opposite side thereof, anda part carried by the hub and having a plane surface engaged by the straight edge ofthe bar so that, the bar when moved in either direction will be wedged between the flat on the cam extension and said pla-ne surface for tain mark or part of the timer cooperating with one of the sets of graduations topoint to a mark of said set of graduations when one of the interrupters begins to function,v

the other interrupter or interrupters being in desired synchronism when the corresponding graduation mark on another set of graduations is adjacent said timer niark or part at the instant the respective interrupter begins a similar Jfunction. v y

6. A synchronizing tool for an'ignition timerhaving a plurality of interrupters, said tool comprising a member to be attached to the timer and having means adapted to cooper-ate With a certainvpart of the 'timer to indicate the synchronistical relation of the i-nterrupters7 the cooperating means including indices on one part and an index upon another part to point to a mark of said indices when one vof the interrupters begins to function, the remaining interrupters being in desired synchronism when an identical function is properly designated by the index and indices. o Inl testimony whereof We hereto affix oui signatures.

JOHN T. Fr'rzsiMMoNs. WILLIAM D. siinorn. 

